Any decline would be the continuation of a trend that has already led to an estimated 15,000 permanent production jobs moving onshore or being eradicated over the past 10 years. But while in the past the offshore numbers have been propped up by increased work in areas such as well development, construction and logistics, these are thought likely to tail off. There are currently about 28,000 offshore workers in the UK’s part of the North Sea, according to the trade association Oil and Gas UK.

James Woodrow, business development manager at Edinburgh-based oil production optimisation specialist Petroleum Experts, said the decline had come as a range of jobs, including production managers, reservoir engineers and geologists, had shifted onshore. Much of their work can now be done remotely through computers.

Woodrow thought this trend would continue, leaving only a skeleton staff of safety engineers and operatives who would be required to manually step in when computer systems went down or in case of an emergency. There are already platforms that can operate unmanned because of their proximity either to other structures or to the shoreline.

Woodrow’s firm will be one of a ­variety exhibiting the latest production automation techniques at the Digital Zone at the Offshore Europe conference in Aberdeen this week, where guests will include Alex Salmond and former BP boss Lord Browne.

Woodrow said: “If you look at companies like StatoilHydro, Shell or Total, they all have what they call collaboration centres, where people sit onshore managing and making decisions. But things are never foolproof. You’ll still have people offshore for when automation systems fail.

“I would roughly estimate that the headcount on standard production platforms has gone down by 50% to 60% over the last eight to 10 years. And it will continue to drop dramatically, perhaps by about another 15% to 20%.

On rough estimates, these figures indicate that around 15,000 jobs have gone onshore or disappeared and that a decline of another 5000 could follow.

Mike Tholen, economic and commercial director at Oil and Gas UK, agreed that the trend would be “gentle decline” in offshore jobs, but thought 5000 might be a little pessimistic.

He said: “Automation is taking a big bite out of the daily running of platforms and other activities. The massive accommodation modules that I remember from the early days are a thing of the past on a number of platforms.

“I certainly agree the trend will continue because having people offshore is expensive, and not where you want them for the most part. But there won’t be a radical collapse. There will still be plenty of work in areas such as logistics and extending the life of existing platforms, not to mention decommissioning.”

Woodrow said manned platforms would also come under challenge because most future investment would go into subsea work in deep waters such as to the west of Shetland, as

easier-to-reach reserves have dwindled.

In such projects, all production is done remotely. Bill Murray, chief executive of the Offshore Contractors Association, recognised the trend but said it was not

affecting the numbers of his members offshore at present. He said: “We are down a bit this year, but that’s more due to the lack of project work coming forward because of the recession.”

He still thought recruitment would be one of the biggest concerns for the industry in years to come. This is generally a hot topic among oil and gas men because a lack of graduate recruitment in the 1990s means the industry has an ageing workforce.

This subject will be one of the key topics for discussion at Offshore Europe, which rotates annually between Aberdeen and Stavanger in Norway. This year’s theme is Energy at a Crossroads, with other subjects including how to satisfy rising hydrocarbon demand from emerging economies, and how to come up with partnership models that

will enable the oil majors to work most efficiently with national oil companies in places such as Saudi Arabia.

As well as the first minister and Lord Browne, speakers include Schlumberger boss Andrew Gould, TAQA chief executive Peter Baker and Danish climate minister and UN Climate Change Conference host Connie Hedegaard.